August Dinner Meeting in Bozeman - Dr. Armin Stuedlein on Axial and Lateral Performance of Drilled Shaft Foundations

Dr. Armin Steudlein, PhD, P.E. is a licensed professional engineer and Professor of Geotechnical Engineering in the School of Civil and Construction Engineering at Oregon State University. Armin received his MS and PhD in geotechnical engineering from Syracuse University (2003) and the University of Washington (2008), respectively. He joined the faculty at OSU in 2009 after consulting for Seattle-based firms, where he specialized in port and harbor engineering with an emphasis on foundation and earthquake engineering. The results of his research have been disseminated through 175+ publications and consultation for PacNW firms and focuses on liquefaction and cyclic softening through dynamic in-situ and cyclic laboratory testing, ground improvement, experimental and numerical investigations of soil-structure interaction, and probabilistic geotechnical analyses. His research is funded by various departments of transportation, the National Science Foundation, and industry partners. He is the Chair of the Soil Improvement Committee (ASCE G-I), outgoing Editor at the ASCE Journal of Geotechnical and Geoenvironmental Engineering, Editor at the Journal of the Deep Foundations Institute, and Editorial Board member for Georisk and the Canadian Geotechnical Journal. Professor Stuedlein received several awards, most recently the 2023 ASCE J. James R. Croes Medal and the 2023 and 2024 Fredlund Awards.

PRESENTATION - Axial and Lateral Performance of Drilled Shaft Foundations Considering High-Strength Reinforcement and Permanent Casing

The amount of steel reinforcement in drilled shaft foundations has increased due to increased axial and lateral loading demands as our understanding of the regional seismic hazard evolves. Consequently, the use of more and/or larger sized bars has increased the possibility of anomalies within drilled shafts due to reduced apertures between congested reinforcements. This presentation discusses the results of a comprehensive full-scale study conducted to evaluate the effects of permanent steel casing and high strength steel reinforcement on the axial and lateral load transfer characteristics of drilled shaft foundations. Pertinent findings and observations from the experimental programs are discussed, including results of various integrity tests, the global axial and lateral load-displacement response, load transfer, and t-z, q-z, and p-y curves. Use of structural hollow bar to serve the dual function of longitudinal reinforcement and access for crosshole integrity testing is described, as well as the results of thermal integrity profiling. Reduced axial load transfer performance of permanently-cased shafts as compared to the uncased shafts is discussed in view of subtle differences in pre-drill auger diameter. The findings on the lateral loading tests establishes the suitability of simplified section analyses to predict the observed moment-curvature response of the shafts, synthesizes casing reduction factors, and demonstrates the that internal steel reinforcements within permanently-cased shafts are unnecessary. The presentation concludes with some opinions on best practices for design of drag loads.

Check-in and social hour begins at 5:00 with drinks available. Food will start between 5:00 and 5:30, and the presentation will begin around 6:15. 

DIRECTIONS: The main entrance to the venue is at 14 S. Tracy , which is on the east side of Tracy Ave in about the middle of the block, two doors north of the alleyway and directly behind the retail space for Athleta (on Main Street). Once inside, you can take the elevator or stairs to the lobby on the 2^nd floor, and we'll be waiting at the reception desk to direct you to the North Ballroom, which is at the east end of the lobby.

We are now offering PDH credits for attending our dinner meeting presentations. This event will count for 2.0 PDH. Certificates will be provided after the event to those who attend and check-in.